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Although pain and fatigue are commonly encountered in clinical practice, their impact on children with MO remains largely unaddressed in literature. This study aimed to (1) assess fatigue and pain levels in children with MO, (2) compare fatigue severity with healthy peers, and (3) identify variables associated with fatigue and pain.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Methods<\/jats:title>\n                    <jats:p>In this cross-sectional study, 230 children (4-18yrs.) with MO were invited to complete validated, age-specific online questionnaires addressing fatigue (Checklist Individual Strength [CIS], visual analogue scale [VAS-fatigue]), pain (VAS), and psychosocial factors. Fatigue scores were compared to reference data from healthy peers using one-sample t-tests. The International Classification of Functioning, disability and health framework was used for a-priori selection of potential independent variables for multivariable regression analysis.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Results<\/jats:title>\n                    <jats:p>\n                      A total of 134 children participated. Fatigue was reported by 89.6% (VAS-fatigue\u2009=\u20093.17\u2009\u00b1\u20092.63), with CIS scores significantly higher than healthy controls (CIS-MO\u2009=\u200966.32\u2009\u00b1\u200924.63 vs. CIS-healthy peers\u2009=\u200955.07\u2009\u00b1\u200920.99,\n                      <jats:italic>p<\/jats:italic>\n                      \u2009=\u20090.012). Pain was reported by 75.4% (VAS\u2009=\u20092.41\u2009\u00b1\u20092.42). For fatigue, both CIS and VAS-fatigue were associated with pain and emotional\/behavioral problems (CIS-model adj. R2\u2009=\u20090.524,\n                      <jats:italic>p<\/jats:italic>\n                      \u2009&lt;\u20090.001; VAS-fatigue model adj. R2\u2009=\u20090.576,\n                      <jats:italic>p<\/jats:italic>\n                      \u2009&lt;\u20090.001). CIS was also associated with depressive symptoms (CDI,\n                      <jats:italic>p<\/jats:italic>\n                      \u2009=\u20090.019). The pain regression model explained 45% of the variance (\n                      <jats:italic>p<\/jats:italic>\n                      \u2009&lt;\u20090.001), and pain was significantly associated with functional disability and VAS-fatigue (\n                      <jats:italic>p<\/jats:italic>\n                      \u2009&lt;\u20090.001).\n                    <\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Conclusion<\/jats:title>\n                    <jats:p>Fatigue, alongside pain, is highly prevalent and significantly increased in children with MO compared to healthy peers. Psychosocial factors are closely associated with both fatigue and pain, underscoring the importance of multidisciplinary disease management.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Clinical trial number<\/jats:title>\n                    <jats:p>Not applicable.<\/jats:p>\n                  <\/jats:sec>","DOI":"10.1186\/s13023-026-04476-2","type":"journal-article","created":{"date-parts":[[2026,6,29]],"date-time":"2026-06-29T11:15:03Z","timestamp":1782731703000},"update-policy":"https:\/\/doi.org\/10.1007\/springer_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Fatigue and pain in children with multiple osteochondromas: a cross-sectional study"],"prefix":"10.1186","volume":"21","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-5464-8636","authenticated-orcid":false,"given":"Ihsane","family":"Amajjar","sequence":"first","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Nienke W.","family":"Willigenburg","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Rob J.E.M.","family":"Smeets","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"S. 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In the Netherlands, individuals aged 16 and above are legally permitted to provide their own informed consent, while those under 16 require consent from their guardian(s). Under the age of 12 the guardians\u2019 consent suffices, while above the age of 12, consent from participants is required as well. Written informed consent was obtained from participants and their guardian(s) as appropriate for each participant\u2019s age. This study was part of a larger project that also evaluated quality of life and physical activity levels in the same population [\n                      \n                      ].","order":1,"name":"Ethics","label":"Ethical approval and consent to participate","group":{"name":"EthicsHeading","label":"Declarations"}},{"value":"Not applicable.","order":2,"name":"Ethics","label":"Consent for publication","group":{"name":"EthicsHeading","label":"Declarations"}},{"value":"The study was supported by the national patient association \u2018HME-MO vereniging Nederland\u2019. The association recruited patients through placing calls on their website and newsletters. The association also cooperated in the assessment of the burden of the study. Once the study has been published, we intend to inform participants of the results through the website of the national patient association and will sent details of the results in a study newsletter suitable for a non-specialist audience. Preliminary results were presented at the 2024 National MO Day, where they were discussed and well received by patients and their families.","order":3,"name":"Ethics","label":"Patient involvement","group":{"name":"EthicsHeading","label":"Declarations"}},{"value":"The authors declare that they have no competing interests.","order":4,"name":"Ethics","label":"Competing interest","group":{"name":"EthicsHeading","label":"Declarations"}}],"article-number":"324"}}